The Organization of the Petroleum Exporting Countries and its allies face stiffening competition in 2020, the International Energy Agency said on Friday, adding urgency to the oil producer group's policy meeting next month.

"The OPEC+ countries face a major challenge in 2020 as demand for their crude is expected to fall sharply," the Paris-based agency said in a monthly report.

"Surging non-OPEC supply explains this drop, with growth of 2.3 million barrels per day (bpd) next year versus 1.8 million bpd in 2019," it added, citing production from the United States, Brazil, Norway and Guyana.

Demand for crude oil from OPEC in 2020 will be 28.9 million bpd, the IEA forecast, 1 million bpd below the exporter club's current production.

The agency kept its assessments for growth in global oil demand in 2019 and 2020 at 1 million bpd and 1.2 million bpd respectively, but said its outlook might slightly underestimate the impact of tariffs from the U.S.-China trade war.